水杨酸钠对爆震性聋治疗作用的实验研究

目的　探讨水杨酸钠(NaSA)对豚鼠爆震性聋的治疗效果及其作用机制。方法　豚鼠分为爆震组、爆震+NaSA组、NaSA组。每组动物12只。爆震动物暴露于平均压力峰值176.7dB(SPL)；水杨酸钠为腹腔注射400mg/kg,每日一次。实验前和实验后第1d、3d、1周、2周、4周分别检测ABR阈值；扫描电镜观察毛细胞形态改变，耳蜗铺片计算毛细胞损伤数；测定耳蜗组织丙二醛(MDA)含量。结果　爆震组于爆震第1d、3d、1周、2周、4周的ABR阈移分别为46.75±13.56、38.0±12.4、35.5±10.67、41.5±12.57、33.75±8.42dB,爆震+NaSA组则分别为46.65±11.7、38.25±9.52、30.5±9.17、30.0±9.8、23.0±6.57dB，两组间于1周，2周，4周显著性差异(P＜0.05)。形态学改变与听阈改变一致，耳蜗铺片计算外毛细胞损失数，两组有显著性差异(P＜0.05)。耳蜗组织MDA检测，两组于2周,4周有显著性差异(P＜0.05)。单纯NaSA给药后24h内ABR阈值有暂时性升高，14h后基本恢复正常。结论　NaSA可部分减轻爆震所致的听力损失。可能因NaSA在一定程度上清除了爆震产生的过量的过氧化物，从而保护毛细胞，使听力得到部分恢复。

An Experimental Study on the Treatment of Blast Deafness by Sodium Salicylale

Objective　To explore the effects of treatment and mechanism of sodium salicylate on blast deafness. Methods　Guinea pigs were divided into blast group, blast plus sodium Salicylate group and sodium solicylate group. The animals in the blast group were exposed to blast average peak pressure 176.7 dB(SPL); sodium salicylate was injected IP 400 mg/kg,1/d. Monitoring ABR threshold, the value of MDA of and counting the number of hair cells on the cochlea preparation, SEM for hair cells was observed. Results　The ABR threshold shift in the blast group was 46.75±13.56 dB，38.0±12.4 dB,35.5±10.67 dB，41.5±12.57 dB,33.75±8.42 dB, post-blast 1 d，3 d，1 w，2 w,4 w respectively. And that of the blast plus sodium salicylate was 46.65±11.7 dB，38.25±9.52 dB,30.5±9.17 dB,30.0±9.17 dB,23.0±6.57 dB. The two groups differed significantly at 1 w，2 w，4 w(P＜0.05). The value of MDA differed significantly at 2 w,4 w(P＜0.05). And the hair cells lost also differed significantly. It was observed that sodium salicylated can raise the ABR thresbold temporarily 24 hrs during simple sodium salicylate adminastration. However it recovered 14 hrs after the injection.Conclusion　Sodium salicylate can partially attenuate the hearing loss caused by blast. It is probable that sodium salicylate can clear peroxicative produced during blast and therefore protect hair cells and make hearing loss partially recover.